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This study examined 100 Arab-American families of children attending a weekly Sunday school in the Southeastern region of the US on their views about infants, toddlers or preschoolers’ touchscreen device usage patterns. Over 80 percent of the respondents have obtained at least a bachelor’s degree. Surveys were completed for 51 boys and 49 girls. Like studies on children of other ethnic groups living in the United States of America show, Arab infants, toddlers and preschoolers’ mobile touchscreen device usage patterns do not conform to the 2016 American Academy of Pediatrics guidelines which suggested no touchscreen device usage for children below 2 years and 1-hour daily usage for children between 2-5 yesrs. However, Arab-American parents hold different views on the use of mobile touchscreens with young children when compared to studies from other parents living in the United States. Also, Arab American parents are less concerned about their infant, toddlers and preschools’ children damage to touchscreen devices. Thus, further studies are required to delineate why Arab American parents’ views on touchscreen devices differ to their young children reported usage habit.

This research examines the relationship between growth, growth disruption, and skeletal indicators stress amongst juveniles (n=60) interred at the Late Antique infant and child cemetery at Poggio Gramignano (PG) (ca. 5th century CE), associated with a rural agricultural community. Growth disruption – evidenced by decreased long bone length compared to dental age – and stress experience – evidenced by skeletal stress indicators – were compared to those within juveniles from two urban Roman-era cemeteries (n=66), Villa Rustica (VR) (0-400 CE) and Tragurium City Necropolis (TCN) (400-700 CE). Results indicate that the PG juveniles had significantly smaller femoral lengths-for-age than VR and TCN; however, the frequency of skeletal stress indicators were higher among juveniles at VR and TCN. These differences in growth and stress experience likely resulted from differing biosocial and ecological environments present in the different regions at the time, including differing nutrition, disease, and socioeconomic structures between urban and rural Roman populations.

Infants 6-8 months old are able to identify nearly every speech sound contrast on which they have been tested, regardless of whether that contrast represents an across-category (two different phonemes) phonetic change in their native language or not. A child's ability to identify non-native consonant contrasts greatly diminishes by 11-12 months of age. The present study examined speech sound discrimination in three groups of listeners. Adult second language (L2) listeners of Spanish were compared with native English listeners with no knowledge of Spanish and native Mexican listeners to determine if they would show the ability to discriminate phonetic distinctions that are present in Spanish and not English. Behavioral and Electrophysiological measures were obtained in response to a continuum of bilabial consonant-vowel (CV) stimuli that differed in voice onset time (VOT) from -50 to 30 ms VOT (/ba/ to /pa/). The -50 ms VOT stimulus was paired with each of the others to form stimulus pairs with varying degrees of acoustic difference. Behavioral data showed that L2 listeners of Spanish perceived a transition from /ba/ to /pa/ later than native Spanish listeners but earlier than English only listeners. Electrophysiological data using the mismatch negativity revealed that the both L2 Spanish and native Spanish listeners perceived a distinction between stimuli in the stimulus pairs 20 ms earlier than English only listeners. These results support the theory that underlying neural-sensory representations of speech may be altered by linguistic experiences, and that the loss of non-native speech sound discrimination abilities in infancy and the regaining of these abilities in adulthood is not due merely to attentional bias.

Hypoplastic left heat syndrome (HLHS) is a complex cardiac malformation in neonates suffering from congenital heart disease and occurs in nearly 1 per 5000 births. HLHS is uniformly fatal within the first hours or days after birth as the severly malformed anatomies of the left ventricle, mitral, and aortic valves, and ascending aorta are not compatable with life. The regularly implemented treatment, the Norwood operation, is a complex open heart procedure that attempts to establish univenticular circulation by removing the atrial septum ( communicating the right and left ventricle), reconstructing the malformed aortic arch, and connecting the main pulmonary artery into the reconstructed arch to allow direct perfusion from the right ventricle into the systemic circulation. A relatively new treatment being utilized,the Hybrid Norwood procedure, involves a less invasive strategy to establish univentricular circulation that avoids a cardiopulmonary bypass (heart-lung machine), deliberate cardiac arrest, and circulatroy arrest of the patient during the procedure. The resulting systemic-pulmonary circulation is unconventional; blood is pumped simotaneously and in parallel to the systemic and pulmonary arteries after the procedure. Cardiac surgeons are deeply interested in understanding the global and local hemodynamics of this anotomical configuration. To this end, a multiscale model of the entire circulatory system was developed utilizing an electrical lumped parameter model for the peripheralor distal circulation coupled with a #D Computational Fluid Dynamics (CFD) model to understand the local hemodynamics. The lumped parameter (LP) model is mainly a closed loop circut comprised of RLC comartments that model cardiac function as well as the viscous drag, flow intertia, and compliance of the different atrial and venous beds in the body. A system of 32 first-order differential equations is formulated and solved for the LP model using a fourth-order adaptive Runge-Kutta solver. The output pressure and flow waveforms obtained from the LP model are imposed as boundary conditions on the CFD model. Coupling of the two models is done through an iterative process where the parameters in the LP model are adjusted to match the CFD solution. The CFD model domain is a representative HLHS anatomy of an infant after undergoing the Hybrid Norwood procedure and is comprised of the neo-aorta, pulmonary roots, aortic arch with branching arteries, and pulmonary arteries. The flow field is solved over several cardiac cycles using an implicit-unsteady RANS equation solver with the k-epsilon turbulence model.; Hypoplastic left heart syndrome (HLHS) is a complex cardiac malformation in neonates suffering from congenital heart disease and occurs in nearly 1 per 5000 births. HLHS is uniformly fatal within the first hours or days after birth as the severely malformed anatomies of the left ventricle, mitral and aortic valves, and ascending aorta are not compatible with life. The regularly implemented treatment, the Norwood operation, is a complex open heart procedure that attempts to establish univentricular circulation by removing the atrial septum (communicating the right and left ventricle), reconstructing the malformed aortic arch, and connecting the main pulmonary artery into the reconstructed arch to allow direct perfusion from the right ventricle into the systemic circulation. A relatively new treatment being utilized, the Hybrid Norwood procedure, involves a less invasive strategy to establish univentricular circulation that avoids a cardiopulmonary bypass (heart-lung machine), deliberate cardiac arrest, and circulatory arrest of the patient during the procedure. The resulting systemic-pulmonary circulation is unconventional; blood is pumped simultaneously and in parallel to the systemic and pulmonary arteries after the procedure. Cardiac surgeons are deeply interested in understanding the global and local hemodynamics of this anatomical configuration. To this end, a multiscale model of the entire circulatory system was developed utilizing an electrical lumped parameter model for the peripheral or distal circulation coupled with a 3D Computational Fluid Dynamics (CFD) model to understand the local hemodynamics. The lumped parameter (LP) model is mainly a closed loop circuit comprised of RLC compartments that model cardiac function as well as the viscous drag, flow inertia, and compliance of the different arterial and venous beds in the body.

Behavioral organization in infants can be characterized by the integration and coordination of component behaviors over time, mediated in part by emerging nervous system activity. This study evaluated the organization of behavioral states and the percentages of time spent in particular behavioral states by preterm infants. In addition, the effects of visual stimulation on the organization of behavioral state and on the development of the visual skills in preterm infants was assessed. Twenty preterm infants were observed at the time of admission and discharge from the intermediate unit of a neonatal intensive care unit. Behavioral state was recorded and visual responsiveness assessed on both occasions. For one group of infants, a striped visual stimulus was placed in their incubators following the initial observation, and removed at the time of the second observation. A second group of control infants received no exposure to the visual stimulus. Results revealed that infants who were exposed to a visual stimulus significantly decreased the number of state changes they experienced and had significantly higher visual responsiveness scores than infants who were not provided a visual stimulus. The amount of increase in the percentage of time spent in Quiet Sleep and increase in the state stability score, a measure of consistency among behavioral states, was nominally higher for infants who were exposed to the visual stimulus than for infants who were not allowed exposure to the visual stimulus. These findings indicate that visual stimulation can influence the development of visual responsiveness in preterm infants. Furthermore, exposure to a visual stimulus appears capable of extending the amounts of time that preterm infants spent in particular behavioral states, thus reducing the number of state changes they experience. The significance of these findings is discussed in terms of preterm intervention procedures. In addition, the possible importance of self-regulation of sensory input for preterm infants and the clinical implications of low and high state stability scores are discussed. / Ph. D.

Preterm birth is a leading cause of both maternal and neonatal morbidity and mortality. It occurs in roughly one in every ten pregnancies, and at an even higher rate among Black Americans and residents of underdeveloped nations. Preterm birth can be initiated in response to a maternal or neonatal indication, or can occur spontaneously. Though indications for the former may vary, the most frequent indication for indicated preterm birth is preeclampsia, a disorder of pregnancy marked by high blood pressure and systemic organ damage. While spontaneous preterm birth and preeclampsia account for a substantial fraction of the burden of prematurity, our understanding of the triggers for and pathogenesis of both diseases are lacking. As a result, we are not able to accurately identify women early in pregnancy who are at high risk of having a spontaneous preterm birth or of developing preeclampsia. There is mounting evidence that local and systemic inflammation, infection, and environmental exposures impact the vaginal ecosystem and may be triggers of spontaneous preterm birth and preeclampsia. In this thesis, I explore the role of vaginal microbes, metabolites, and immune factors in spontaneous preterm birth and preeclampsia. After reviewing what is known about the vaginal ecosystem in spontaneous preterm birth and preeclampsia, I present a paired study of the vaginal microbiome and metabolome in a cohort of 232 women, 80 of whom delivered spontaneously preterm, and whose vaginal ecosystems were profiled during the second trimester of pregnancy. In this study I identify several metabolites strongly associated with spontaneous preterm birth, and suggest that many of these may be exogenous in origin. I also use metabolic models to investigate tyramine, a metabolite found to be associated with lower risk of spontaneous preterm birth. Finally, using predictive models I show that vaginal metabolite levels can be used to identify women at risk of spontaneous preterm birth months in advance. I then present a second study of the vaginal microbiome and immune factors in a cohort of 124 women, 62 of whom developed severe preeclampsia, and whose vaginal ecosystems were profiled at the end of the first trimester. In this study, I demonstrate for the first time that the levels of vaginal microbes early in pregnancy as well as genomic variation in the vaginal microbiome are associated with the risk of developing preeclampsia. I also identify that many vaginal immune factors are significantly depleted in the vaginal ecosystem of women who develop severe preeclampsia. I then use predictive models to show that the levels of vaginal microbes are modestly predictive of preeclampsia risk, and that features from the vaginal ecosystem can be used to improve current methods for the identification of women at risk for severe preeclampsia. Finally, I show that the microbiome signature associated with severe preeclampsia replicates in an independent cohort, suggesting that the early pregnancy vaginal microbiome is robustly associated with the diagnosis of preeclampsia months later in pregnancy. Overall, the microbial and molecular signatures that I identify in these studies contribute novel insight to our understanding of the signs and pathogenesis of both spontaneous preterm birth and preeclampsia, and in doing so, suggest novel approaches to intervention and diagnosis.

This thesis examines the effects of formal musical experience in infancy on musical, social and communicative development. Parents and care-givers have a wide-range of choices of activities and products for an enriched musical experience for their infants, yet prior to the studies in this thesis little was known of the effects of formal musical experience on development. In chapter 1, I outline the introduction to my thesis. In Chapter 2, I examine the effects of Kindermusik training on rhythmic enculturation. Infants who participated in these classes demonstrated a heightened interest in rhythmic patterns but also showed a stronger preference for duple metrical patterns, indicating that musical classes for infants can accelerate the development of culture-specific metrical perception. In Chapter 3, I present results showing that infants who participate in active musical classes showed superior development of prelinguistic communicative gestures and social behaviour as compared to infants assigned to a passive musical experience. In Chapter 4 I examine the development of joint attention in infants assigned to active and passive musical experiences. Although no significant results were found, I suggest that either more sensitive measures or a longer period of study might well show differences between the groups. Together these findings indicate that infants are able to engage in meaningful musical training when the developmentally appropriate pedagogical approach is used, and that formal musical experience in infancy can enhance culture-specific musical acquisition as well as impact social and communication development. / Thesis / Doctor of Philosophy (PhD)

Preterm infants are not able to tolerate full enteral feeding of breast milk due to gut immaturity. To fill this nutritional gap, parenteral nutrition is introduced while enteral feeding is gradually increased. Of parenteral nutrition, lipid emulsions supply energy, essential and polyunsaturated fatty acids, which significantly affect short- and long-term health outcomes of growth, visual-and neuro-development for preterm infants. However, elevated plasma triglyceride (TG) levels in preterm infants receiving lipid emulsions have been observed despite less lipid intake compared to breast milk fed infants. We hypothesized that unbalanced fatty acid profiles in lipid emulsion was one factor to cause high plasma TGs for preterm infants. In the multi-center, observational, prospective study, the following samples were analyzed using GC-MS: (1) lipid emulsions (n=5) and breast milk (n=112), (2) plasma (n=294) including normal TG (n=116) and high TG (n=88). Lipoproteins in normal TG (n=18) and high TG (n=24) plasma were measured using gel electrophoresis. Fatty acid profiles in lipid emulsions differed from ones in breast milk. Plasma fatty acid profiles were related to dietary fatty acid intake. Accumulation of all fatty acids except C20:5n3 and relatively high (LDL+VLDL) levels (p<0.001) resulted in high TG plasma compared to normal TG plasma. Overall, this study supports the hypothesis that nutrition of lipid emulsions was associated high TG with differences in fatty acid uptake but it is still unclear if the imbalance of fatty acids directly causes high TG. More research is necessary to investigate other factors such as enzyme activity, lipid clearance rate, or different rate of fatty acid metabolism. / Thesis / Master of Science (MSc)

Данная работа посвящена исследованию особенностей сенсомоторного и когнитивного развития недоношенных младенцев. Недоношенность рассматривается как симптомокомплекс, который реализуется за счет многих разнообразных механизмов. На основе работ отечественных и зарубежных авторов проведен анализ наиболее часто встречающихся форм неинфекционных перинатальных патологий, в частности недоношенности. В эмпирическом исследовании с помощью однофакторного дисперсионного анализа было проведено сравнение показателей уровня развития сенсомоторных и когнитивных функций у доношенных и недоношенных младенцев в возрасте от 6 до 13 месяцев. Для реализации исследования были сформированы три группы: экспериментальная (недоношенные дети) и 2 контрольных группы (соответствующие по хронологическому и гестационному возрасту). На основе полученных данных делается вывод, что недоношенные дети демонстрируют отставание в развитии моторики при типичном развитии когнитивных функций. / This work is devoted to research of sensorimotor and cognitive development in premature infants. Prematurity is considered as a set of symptoms, which is being implemented by many mechanisms. It was analyzed the most common forms of non-infectious perinatal pathology, particularly prematurity using the works of Russian and foreign researchers. It was conducted comparison of the level of development of sensorimotor and cognitive functions in term and preterm infants aged 6 to 13 months using one-way ANOVA. Three groups were formed: experimental (premature babies), and two control groups (corresponding to chronological and gestational age). It was shown that preterm infants have delay in motor development and typical development of cognitive functions.